Variables associated with stability after Le Fort I osteotomy for skeletal class III malocclusion

Stepwise surgical management of binder syndrome with skeletal class III malocclusion in adults

Our study aimed to evaluate a stepwise treatment of class III malocclusion accompanied with flat nasal deformity, using orthodontics, orthognathic surgery, and rhinoplasty, as well as stability during long-term follow-up. In total, 27 patients with nasomaxillary hypoplasia and skeletal class III malocclusion were enrolled in this study. All patients had accepted orthodontic and orthognathic surgery, followed by rhinoplasty with costal cartilage as the second surgical procedure. Clinical results were evaluated by radiography, medical photography, questionnaire, and cephalometric analysis. All patients were satisfied with the surgical results and no serious complications occurred. During the follow-up, the patients showed well-corrected midface contour and nasal projection, and stable occlusion. The costal cartilage grafts were well fixed, without obvious absorption deformation. Lateral cephalometric analysis and overlay results showed that the postoperative point A had advanced approximately 5.20 ± 1.43 mm and the SNA angle had increased by approximately 5.59 ± 2.86°. Soft-tissue measurements showed a 14.22 ± 6.56° decrease in the facial lobe, while the nasolabial angle had increased by 16.83 ± 6.65° postoperatively. The results suggested that stepwise orthodontic-orthognathic surgery and rhinoplasty produce a predictable and stable result in long-term follow-up.

Characterization of labiomandibular movements induced after isolated LeFort I osteotomy in the surgical management of class III malocclusion

INTRODUCTION

Maxillary surgery alone can be proposed for the surgical management of class III malocclusion, but anticipating outcomes for the labiomental muscle complex is challenging due to the mandibular autorotation phenomenon. The objective of this study was to quantify the mandibular and labiomental movements induced by maxillary osteotomy alone in the management of class III malocclusion according to different clinical and surgical variables.

METHODS

The post-operative changes in mandibular and labiomental shapes were studied by geometric morphometry from the pre- and post-operative lateral cephalometric radiograph of 25 patients. The explanatory variables tested were maxillary advancement, maxillary rotation, and divergence.

RESULTS

Soft tissues repositioning are different from postoperative mandibular repositioning after maxillary osteotomy. Neuromuscular adjustments of mandible depend on divergence and the maxillary rotation. Labiomental response only depends on divergence.

CONCLUSION

The surgical procedure does not have the same bone-related and musculocutaneous effects on patients with the same class III malocclusion. It is therefore essential for surgeons to understand the effects of their procedure on musculocutaneous tissues in order to best anticipate post-operative outcomes.

Postoperative skeletal stability at the one-year follow-up after splintless Le Fort I osteotomy using patient-specific osteosynthesis versus conventional osteosynthesis: a randomized controlled trial

The purpose of this study was to assess the 1-year skeletal stability of the osteotomized maxilla after Le Fort I surgery, comparing conventional osteosynthesis with patient-specific osteosynthesis. Patients were assigned to a conventional or patient-specific osteosynthesis group using prospective randomization. The primary outcome was the three-dimensional change in postoperative skeletal position of the maxilla between the 2-week and 1-year follow-up cone beam computed tomography scans. Fifty-eight patients completed the protocol for the 2-week postoperative analysis, and 27 patients completed the 1-year follow-up study protocol. Of the 27 patients completing the entire protocol, 13 were in the conventional group and 14 in the patient-specific osteosynthesis group. The three-dimensional translation analysis showed that the use of the patient-specific osteosynthesis resulted in a skeletally stable result, comparable to that of conventional miniplate fixation. For both the patient-specific osteosynthesis and conventional miniplate fixation groups, median translations of less than 1 mm and median rotations of less than 1° were observed, indicating that both methods of fixation resulted in a stable result for the 27 patients examined. For the Le Fort I osteotomy, the choice between patient-specific osteosynthesis and conventional osteosynthesis did not affect the postoperative skeletal stability after 1 year of follow-up.

Is Cleft Lip or Palate a Risk Factor for Perioperative Complications in Orthognathic Surgery?

PURPOSE

Perioperative outcomes following cleft orthognathic surgery are not well established. The purpose of this study was to compare the incidence of orthognathic specific complications (OSCs) in patients with and without cleft lip and/or palate.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program adult and pediatric databases were used to enroll patients undergoing orthognathic surgery. The primary predictor variable was a prior diagnosis of cleft lip and/or palate: cleft versus noncleft. The primary outcome variable was OSCs (yes/no) within 30 days of the index operation. Descriptive, bivariate, and multiple logistic regression statistics were computed to measure the association between cleft status and OSCs.

RESULTS

The study sample was composed of 1,149 subjects: 98 in the cleft group and 1,051 in the noncleft group. The incidence of OSCs was 6.1 and 4.7% for the cleft and noncleft groups, respectively (P = .461). After adjusting for age, cleft status, bone grafting, segmentation of the maxilla, and history of bleeding disorder, classification as American Society of Anesthesiologists (ASA) III (P = .002, odds ratio [OR] = 3.92, 95% confidence interval [CI] 1.63-9.40), ASA IV (P = .039, OR = 9.47, 95% CI 1.12-80.4), and isolated mandibular osteotomies (P = .006, OR = 3.23, 95% CI 1.40-7.48) were independent predictors of OSCs. Length of stay was 1.66 ± 1.14 days compared to 1.37 ± 3.74 days for the cleft and noncleft groups, respectively (P = .443).

CONCLUSIONS

There was no significant difference in the incidence of perioperative OSCs and length of hospital stay between cleft and noncleft patients. Cleft status was not an independent predictor of OSCs; instead, greater ASA classification and isolated mandibular osteotomies were the only predisposing factors. Patients with clefts undergoing orthognathic surgery do not have an increased risk of short-term OSCs within the limitations of this study.

One-Year Stability of LeFort I Advancement in Patients With Complete Cleft Lip and Palate Using a Standardized Clinical and Surgical Protocol

AIM

To assess treatment outcome and 1-year stability of LeFort I advancement in patients with complete cleft lip and palate.

METHODS

Thirty-five patients (age 20.65 ± 2.20 years) with unilateral (n = 25) or bilateral (n = 10) complete cleft lip and palate who underwent LeFort I advancement were included.Lateral cephalograms before surgery (T1), immediately postsurgery (T2), and at 1-year follow-up (T3) were superimposed, and the position of anterior nasal spine (ANS), A-point, and U1 Tip assessed using an x, y coordinate system. Differences between landmark positions at the 3-time points were analyzed using paired sample t-tests, with a significance defined as α ≤ 0.05.

RESULTS

The mean surgical advancement in the horizontal direction (T2-T1) was 6.50 ± 2.62 mm at ANS (P < 0.001) and 7.05 ± 2.51 mm at A-point (P < 0.001). At a 1-year follow-up (T3-T2), the mean horizontal relapse at ANS was -1.41 ± 1.89 mm (P < 0.001) and -0.79 ± 1.48 mm at A-point (P 0.003). Mean horizontal relapse was 21.7% and 11% of surgical advancement when assessed at ANS and A-point, respectively. The central incisor tip position remained stable during the postsurgical period (0.12 ± 2.11 mm, P 0.732). At A-point, the mean vertical surgical change (T2-T1) was -0.96 ± 2.57 mm (P < 0.001). No significant post-treatment (T3-T2) vertical changes were detected at ANS or A-point. Phenotypic stability was excellent, with all patients maintaining positive overjet at 1-year follow-up.

CONCLUSIONS

LeFort I advancement in complete cleft lip and palate is stable, with less than a 2 mm relapse after 1-year. Surgical overcorrection by 10% to 20% is recommended to compensate for the expected skeletal relapse.